How do you graph $y=cos4x$ ?

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Answer 1 · 2016-09-30T11:46:54

The period of the cosine wave y = cos kx = $2/kpi$ .

Here, for y = cos 4x, the period is $(2pi)/4=pi/2$

Let us make a Table, with spacing $pi/16$ .

for one period $x in [0, pi/2]$

$(x, y): (0, 1) (pi/16, 1/sqrt 2) (pi/8, 0), (3/16pi, -1/sqrt 2) (pi/4, -1)$

$(5/16pi,. -1/sqrt 2) (3/8pi, 0) (7/16pi, 1/sqrt 2) (pi/2, 1)$

The graph for this Table will show one full wave.

Foe successive periods, move this graph laterally ( in the x-

direction), through $pi/2 =1.57$ units..

How do you graph y=cos4xy=cos4x?